$('#fullscreen').on('click', function (e) {
	    var element = document.documentElement;     // 返回 html dom 中的root 节点 <html>
	    
	    if(!$('body').hasClass('full-screen')) {
	        $('body').addClass('full-screen');
	        $('#alarm-fullscreen-toggler').addClass('active');
	        // 判断浏览器设备类型
	        if(element.requestFullscreen) {
	            element.requestFullscreen();
	        } else if (element.mozRequestFullScreen){   // 兼容火狐
	            element.mozRequestFullScreen();
	        } else if(element.webkitRequestFullscreen) {    // 兼容谷歌
	            element.webkitRequestFullscreen();
	        } else if (element.msRequestFullscreen) {   // 兼容IE
	            element.msRequestFullscreen();
	        }
	        // 切换全屏按钮
	        $('#fullscreen').html('<i class="layui-icon layui-icon-screen-restore"></i>');
	    } else {            // 退出全屏
	        console.log(document);
	        $('body').removeClass('full-screen');
	        $('#alarm-fullscreen-toggler').removeClass('active');
	        //  退出全屏
	        if(document.exitFullscreen) {
	            document.exitFullscreen();
	        } else if (document.mozCancelFullScreen) {
	            document.mozCancelFullScreen();
	        } else if (document.webkitCancelFullScreen) {
	            document.webkitCancelFullScreen();
	        } else if (document.msExitFullscreen) {
	            document.msExitFullscreen();
	        }
	        // 切换全屏按钮
	        $('#fullscreen').html('<i class="layui-icon layui-icon-screen-full"></i>');
	    }
	});